Carburetor



CARBURETOR Filed Aug. 4, 1960 F. K. H. NALLINGER ...m m m M M m 4 M 4. n., F m 4 u 2 m i n i n y l July 6, 1965 3,192,944 CARBURETOR Friedrich K. H. Nallinger, 5 Albrecht-Durer-Weg, Stuttgart, Germany Filed Aug. 4, 19,60, Ser. No. 46,617 Claims priority, application Germany, Aug. 8, 1959,

N 17,071 4 Claims. (Cl. 137-375) The present invention relates to a carburetorfor interlnal combustion engines, especially for motor vehicles,

None -of these past elorts has, however, been fully successful.

vIt is an object of the present invention to overcome the above-mentioned disadvantages -by screening off the fuel at the inside ofthe float chamber of the carburetor relative to the ysurrounding router air by providing the float 'I chamber and, if desired, also the cover thereof with heatinsulatng and/or heat-dissipating means.

' The present invention thus prevents the fuel from being heated and coming to the boiling point Within the float chamber by the often very high temperature of the 'air underneath the engine hood, and it has the advantage'that l'the carburetor itself may remain in the usual place provided for it.

According to the invention, the float chamber itself may consist entirely or partly of a heat-insulating material and it may form a separate housing which is secured to the metallic body of the carburetor, for example, by being `flanged thereto. According to .another embodiment of the invention, one wall, that is, either the outer or inner wall, of the metallic housing containing the float chamber Many efforts have in the past been made to overcome this carburetor boiling by mounting the carburetor and its connecting lines in special positions and also by supplying it with a cool fuel.

United States Patent O may be coated with a heat-insulating material. The heatinsulating material may in either case consist of plastic, rubber, glass, or of materials having equivalentV heatinsulating properties.

In the event of a coating, there are various possibilities `of applying the sameto the respective wall of the housing containing the -oat chamber, for example, by spraying it thereon. Th same effect may also be attainedby providing a separately produced container of heat-insulating material and by either inserting this container into the metal housing or by fitting it over the outside thereof.`

The first mentioned possibility, that of applying a coating, may be of a greater advantage insofar as it may be more easily produced since the metal housing of the iioat chamber including its cover may then be coated with the heatinsulating material, for example, in the same manner in which paint is applied, after the metal housing has been finally installed in the car or other motor vehicle.

According to a further embodiment of the invention, the actual float chamber within the housing may be separated frorn the outside .air by providing an intermediate space between the walls of the chamber and housing. One of these wall-s may then be made of a heat-insulating material or be provided with a coating of such a material. This last-mentioned embodiment of the invention has the particular -advantage that the intermediate space between the two walls may be used as a cooling chamber ice through which a cooling medium may be passed. This cooling medium preferably consists of the engine fuel itself.. The regular fuel-pump of the engine or an additional pumpmay then be used for circulating a cooling current of fuel through the space between the two walls of the housing and oat chamber, and this cooling current may lbe supplied in shunt with the main fuel supply and it may also be controlled automatically in accordance with the outer temperature around the carburetor and, if desired, also in accordance with the movement of the vehicle.

These and additional objects, features, and advantages of the present invention will become further apparent from the following detailed description thereof, particularly when the same is read with reference of the accompanying drawings, in which:

FIGURE lfshows a cross section of .a float housing and FIGURES 2 to 4 `show cross sections of three different modifications of the lioat housing, parts of which are broken away.

Referring to FIGURE 1 of the drawings, the carburetor 10 which is generally of a conventional type and only partly shown comprises a housing 11 forming the -oat chamber which is closed .at its upper side by `a c-over 13. This cover 13 -or the housing 11 may be integral with the remainder :of the carburetor and the respective other part may be made separately and flanged to the main part. The float housing 11 contains the float 12 which actuates the valve member 14 of an inlet valve 15 of plastic.V This valve 15 forms a separate insert in the cover 13. The latter is also provided with a connecting socket 17 to which the fuel line is to be connected. Float chamber 11 is 'adapted to contain the fuel up to a certain level 16 which remains uniform at all times. All of these parts are conventional and do not by themselves form any feature of the present invention.

According to the present invention, the float housing f 11 and, if desired, also the cover 13 thereof may consist either entirely or partly of a heat-insulating material, for

example, a plastic or any other material, for example, glass, which is equivalent thereto insofar as its heat-insulating properties are concerned. The float housing and the cover may be produced separately of each other and be connected in a suitable manner to each other and possibly also to the main body of the carburetor. The fuel is therefore insulated within the oat chamber from the heat ofthe outer air.

According to the embodiment of the invention illustrated in FIGURE l, the housing 11 itself may be made in the usual manner of metal and be provi-ded at t-he inside with a lining 18 of heat-insulating material.V This lining 18 may be formed, for example, by spraying the,

fitted into housing 11 and may be secured and sealedV therein, for example, by a gasket, not shown, which `is `secured by cover 13.

All that -hasbeen said and will hereafter be said about the inner wall of the float housing 11 may also apply in a similar manner to the outer wall thereof. This outer wall and the cover 13 as well may therefore also be similarly provided with a heat-insulating layer, which may be applied, for example, after both parts have been finally assembled and installed and in any manner similar to those in which paint coatings are usually applied.

According to the embodiment of the invention as illustrated in FIGURE 2, the housing 11 containing the oat chamber is also made as an element separate from the remainder of the carburetor which is to be secured to the cover, not shown. Housing 11' is provided with a double wall and may consist either entirely or partly of heatinsulating material or of metal. Especially in t-he latter case, the space 19' between the inner wall 20 and the outer wall 2 will serve as a heat insulation, while in the former case it will serve as an additional insulation.

The screening effect of this double-wall housing may be further improved by conducting a current of a cooling medium through the space `19 between the two walls 2G and 21. Housing Il may for this purpose be provided with an inlet socket 22 and an outlet socket 23 into which the ends of the requiredconnecting pipes may be inserted. The cooling medium may consist, for example, of the fuel used for the operation of the engine. In this event, sockets 22 and 23 may be connected either to the normal fuel pump of the engine or to an additional pump which always circulates a certain amount of fuel through the space 19Ybetween Walls 20 and 21 so that the iioat chamber at the inside of housing 11' will thus always be kept cool.

Such a double-wall housing may, if desired, be additionally coated with a heat-insulating layer which is preferably applied to the outer wall 21 so that the cooling medium in the space 19 between walls 2t) and 21 will not be affected by the high outer temperature but will be able to exert an effective cooling action upon the iloatY chamber in housing 11. The screening effect ofthe walls of the housing will therefore be still `further improved.

As illustrated in FIGUREI3, the heat-insulating part may also be made as a separate element whichV is provided with outer and inner walls and an intermediate space 19 between these walls. This element which may consist entirely of heat-insulating material is fitted tightly over the outer wall of the metallic float housing 11" and is secured in any suitable manner thereto. It may also be provided with connecting sockets similarly as shown in FIGURE 2 for circulating a current of a cooling medium through the space 19". If desired, the float housing 11 may then in addition be provided with double walls, and the cooling medium may then be passed through the space 19 in'one or both elements.

According to the further embodiment of the invention, as illustrated in FIGURE 4, the heat-insulating layer 25 itself which may be made of plastic or equivalent material forms one of two Walls'of the oat housingand is tightly sealed at its tianged upperend 25 to the metallic housing 11 so as to leave a suitable spacebetween the two Walls. This Vouter jacket 25'may also be provided with connecting sockets similarly as shown in FIGURE 2 for circulating a cooling medium through the intermediate space. Jacket 25 may be removably secured to the metallic ioat housing 11 by its ange 26 so as to be exchangeable or it may be permanently secured thereto. Instead ofmounting the heat-insulating member 25 in the form of a jacket on the outside of the metallic container 11 so as to leave an intermediate cooling space between the two members, it is of course also possible to reverse the position of t-he two members so that the heat-insulating member 25 will be inserted into the metallic container ll" and form the actual float chamber.

Although my invention has been illustrated and described with reference to the preferred embodiments thereof, I wish to have it understood that it is in no way limited to the details of such embodiments, but is capable of numerous modifications within the scope of the appended claims.

Having thus fully disclosed my invention, what I claim is:

1i.. In a carburetor for internal combustion engines with a float chamber forming a metallic cotainer having wall portions including a cylindrical wall and a circular imperforate bottom wall, means for insulating the inside of said chamber from the heat of the outside of said chamber comprising a bollo-w heat-insulating member having further wall portions including a further cylindrical wall and a further circular imperforate bottom wal, at least one of said further wall portions being detachably seated in surface contact with one of said firstnamed wall portions.

2.,In a carburetor as defined in claim 1, the outer diameter of said fur-ther cylindrical wall beingY substantially equal to the inner diameter of said first-named cylindrical wall, the `outer surfaces of said further circular `imperforate bottom wall and said further cylindrical wall being respectively detachably seated in surface contact with the inner surfaces of said first-named circular imperforate bottom wall and said first-named cylindrical wall.

3. In a carburetor as defined in claim 1, said further vcylindrical wall being constituted by a double wall comprising an inner wall member and an outer wall member parallel thereto and spaced therefrom, said further circular imperforate bottom wall being constituted by a further double wall comprising a further inner wall member merging with said first-named inner wall'member, said further double wall also comprising a further outer Wall member parallel with and spaced from said further inner wall member, said further outer wall member merging with said first-named outer wall member, and wall means joining said inner and outer wall members of said further cylindrical Wall, said wall means with all vof said inner and outer wall members defining a closed container adapted to contain a cooling medium.

4. =In a carburetor -as defined in claim 1,` said further cylindrical wa-ll and said circular imperforate bottom wall defining with said rst-named cylindrical wall and said first-named circular imperforate bottom Wall a space adapted to contain a cooling medium, means for closing said space comprising mutually abutting portions of said first-named cylindrical wall and said further cylindrical Wall.

References Cited by the Examiner UNITED STATES PATENTS 1,454,730 5/23 DeLukacsevics et al.

2,154,033 4/39 Cameron 261-72 X 2,315,879 4/43 St. Clair 261-72 X 2,899,943 8/59 Haensel 261-65 M. CARY NELSON, Prmry Examiner.

HERBERT L. MARTIN, EUGENE F. BLANCHARD,

xaminers. 

1. IN A CARBURETOR FOR INTERNAL COMBUSTION ENGINES WITH A FLOAT CHAMBER FORMING A METALLIC CONTAINER HAVING WALL PORTIONS INCLUDING A CYLINDRICAL WALL AND A CIRCULAR IMPERFORATE BOTTOM WALL, MEANS FOR INSULATING THE INSIDE OF SAID CHAMBER FROM THE HEAT OF THE OUTSIDE OF SAID CHAMBER COMPRISING A HOLLOW HEAT-INSULATING MEMBER HAVING FURTHER WALL PORTIONS INCLUDING A FURTHER CYLINDRICAL WALL AND A FURTHER CIRCULAR IMPERFORATE BOTTOM WALL, AT LEAST ONE OF SAID FURTHER WALL PORTIONS BEING DETACHABLY SEATED IN SURFACE CONTACT WITH ONE OF SAID FIRSTNAMED WALL PORTIONS. 